OK, this is really crazy so I want to make sure it gets posted to the group so
that the next sap who falls prey to the "gremlin" won't get hung up on it as
long as I was.
This response from Selwyn Hollis solved my problem:
Hi Mary Beth,
I wonder if this is related to a gremlin that I've seen/dreamed on a
few occasions. This one is cured by entering
Needs["Graphics`Graphics`"] and the desired graphics command in
separate cells.
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Selwyn Hollis
That did it, thanks!